COCOMO 81 Intermediate Model Implementation

This is a simple implementation of the Intermediate COCOMO 81 model. You enter software project level information and this program estimates the effort and the schedule required to develop the software product. This model is described in Software Engineering Economics by Barry W. Boehm, Prentice-Hall, 1981.

Software Product Size

The model uses a product size expressed in source lines of code (SLOC). The bigger the size the larger the effort and the longer the schedule. Please enter the size in SLOC:

Software Development Mode

The software project needs to be described with one of three development modes. These modes range from the familiar to the ambitious, tightly constrained development projects.
  • Choose Organic for relatively small teams developing software in a highly familiar, in-house environment.
  • Choose Semi-Detached when the team members have some experience related to some aspects of the system under development but not others and the team is composed of experienced and inexperience people.
  • Choose Embedded if the project must operate within a strongly coupled complex of hardware, software, regulations, and operational procedures, such as real-time systems.
Choose one: Organic Semi-Detached Embedded

Software Development Cost Drivers

There are four categories of cost drivers that are found significant performance predictors for a software development project. Each category has several cost drivers. Each driver has a possible rating from Very Low (VL) to Extra High (XH). The ratings are used in the model to adjust the baseline development effort estimation up or down.

For HELP on each cost driver, select the driver name.

Product Attributes
VL L N H VH Required Reliability
L N H VH Database Size
VL L N H VH XH Product Complexity

Computer Attributes
N H VH XH Execution Time Constraint
N H VH XH Main Storage Constraint
L N H VH Virtual Machine Volatility
L N H VH Computer Turnaround Time

Personnel Attributes
VL L N H VH Analyst Capability
VL L N H VH Applications Experience
VL L N H VH Programmer Capability
VL L N H Virtual Machine Experience
VL L N H Programming Language Experience

Project Attributes
VL L N H VH Modern Programming Practices
VL L N H VH Use of Software Tools
VL L N H VH Required Development Schedule


Effort = 0.0 Person-Months
Schedule = 0.0 Months
Effort Adjustment Factor (EAF) = 1.00

Thank you for your interest in this model.

Created by Brad Clark and Ray Madachy, 1995-2020
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